点击查看 leetcode 题目地址

我的实现：

<?php

function removeDuplicates($s, $k)
{
    echo "一次循环\n";
    $modify = false;
    for ($i = 0, $j = 1; strlen($s) >= $k && $j < strlen($s);) {
        if ($s[$j] == $s[$i]) {
            if ($j - $i == $k - 1) {
                $s = substr($s, 0, $i) . substr($s, $j + 1, strlen($s) - $j - 1);
                $i = $j - $k + 1;
                $j = $j - $k + 2;
                echo "处理之后的字符串:$s, $i, $j\n"; 
                $modify = true;
                //return removeDuplicates(substr($s, 0, $i) . substr($s, $j + 1, strlen($s) - $j - 1), $k);
            }
            $j++;
        } else {
            $i = $j;
            $j++;
        }
    }
    if ($modify == true) {
        return removeDuplicates($s, $k);
    }
    return $s;
}

$s = "pbbcggttciiippooaais";
echo "原始字符：",$s;
$k = 2;
echo removeDuplicates($s, $k);